Many receptors which are involved in controlling pathologic conditions are coupled to G-proteins (Pierce, K. L., et al, Nature Review (Molecular Cell Biology) 3, 639-650 (2002)). These are called G-protein coupled receptors (GPCRs). The GPCRs include α-adrenergic receptors, β-adrenergic receptors, opioid receptors and prostaglandin receptors. Over time, when agonists are administered to activate the receptors, the receptors become desensitized, i.e., agonist administration no longer results in therapeutic activation of receptors and the receptors regardless of agonist administration are unable to control the pathologic condition.